Method and apparatus for solid organ tissue approximation

ABSTRACT

Surgical bolts are useful for solid visceral wound hemostasis. The devices utilize flexible, variable depth transfixing bolts that penetrate the viscera. These bolts bring the tissue into apposition and hold said tissue in apposition while the wound heals. These bolts, or soft tissue rivets, overcome the limitations of sutures that are currently used for the same purposes. The devices are flexible, bendable, and conformable in their wet or dry state. The bolts include pressure plates that are capable of exerting compressive pressure over broad areas of visceral wounds without causing tearing of the friable parenchyma. The bolts are placed and removed by open surgery or laparoscopic access. The bolts can be placed into tissue where both sides of the bolt are exposed, or they can be placed blindly into tissue where the bolt does not protrude out of the tissue at its distal end.

RELATED APPLICATIONS

This application is a continuation of U.S. patent application Ser. No.11/821,323, now U.S. Pat. No. 8,114,124, which is a continuation-in-partof, and claims priority benefit from, U.S. patent application Ser. No.10/358,735 filed Feb. 4, 2003, now U.S. Pat. No. 7,235,090, entitled“Method and Apparatus for Solid Organ Tissue Approximation”, the entirecontents of which are hereby incorporated herein by reference.

FIELD OF THE INVENTION

The field of this invention relates to devices and methods for traumaand general surgery, combat medicine, and emergency medical services.

BACKGROUND OF THE INVENTION

As recently as the early 1990s, surgical operations for trauma weredirected at the anatomic repair of all injuries at time of the initialoperation. It was observed during these exercises that many patientsbecame hypothermic, acidotic, and coagulopathic. Patients showing thesethree signs often died. Death often occurred in the operating room dueto exsanguination, or postoperatively, due to the complications ofprolonged shock and massive transfusion to replace blood lost as aresult of the trauma.

One of the most notable developments in the recent evolution of surgeryhas been the reintroduction of the concept of staged laparotomy toovercome the deficiencies of the repair all-at-once approach. This newstrategy of staged laparotomy employing new tactics that have beentermed damage control is now used in 10% to 20% of all traumalaparotomies.

This strategy opens the way for a variety of new devices and methods forcontrol of hemorrhage from solid organs or viscera. Although there areprocedures for controlling these injuries, none of these proceduresutilize optimal devices or tactics in their execution. Each area offerstechnological opportunities to improve the devices and procedures forapplying those devices.

Sources of hemorrhage within the abdomen that are most difficult tomanage include major stellate fractures in the thick, solid, parenchymalorgans, especially the liver. Such injuries may involve more than onehepatic lobe, involve massive hemorrhage, and may be caused by severeblunt or penetrating trauma. While the control of most liver hemorrhageis simple, these very severe anatomic wounds are difficult to manage andhave a high mortality, sometimes exceeding 80%. Standard approaches tocontrol of these wounds involve packing with gauze or omentum, ifavailable, and deep liver sutures. Each of these techniques has seriouslimitations and often fails. A major technical problem has to do withthe depth to which the sutures can be placed within the liver. Thelimitation of liver sutures to coapt tissue edges or tamponade deepparenchymal wounds is clear for several reasons. Sutures may be attachedto or come pre-mounted to needles of limited size and curvature makingdeep placement difficult or impossible. The sutures tend to tear throughthe friable parenchyma. Another problem with sutures is that since theyneed to be tied off to themselves or other sutures, they form a circularconfiguration around certain tissues and may strangulate the tissueswithin that circle. This strangulation causes reduced blood flow andpotentially damaging ischemia for those tissues. In addition, the suturedoes not distribute its force adequately to compress tissues outside ofa very narrow plane described by the circle of the suture path. Anotherkey problem with the current treatment is the time taken to achievesuture hemostasis. Massive bleeding must be stopped quickly or thepatient will exsanguinate and die. Placement of sutures is a timeconsuming process given the tools available today, the friable nature ofparenchymal tissue, and the undesirability of intra-hepatic gauzepacking.

The size and curvature of currently marketed needles is pre-set by themanufacturer. Current needles are not long or big enough to transfixmajor liver lacerations. Even if the needle was large, the suture methodof repair causes inadequate force distribution to create hemostasis andresist progressive wound tearing.

New devices, procedures and methods are needed to support the strategyof damage control in patients who have experienced massive visceralinjury. Such devices and procedures are particularly important in theemergency, military, and trauma care setting. These new devices,specifically parenchymal bolts, rely on the principles of broad forcedistribution on the tissue, pressure tamponade, ease of placement, easeof locking in place with the pressure pads, the ability to adjusttension to optimize tissue compression, and the lack of progressivetearing of the friable wound due to the high shear caused by the suture.

SUMMARY OF THE INVENTIONS

This invention relates to an improved haemostatic tissue appositiondevice for use in trauma care. The present invention is a transfixingtrans-parenchymal bolt. Key features of the bolt include columnstrength, adjustable depth of penetration, flexibility, tissuenon-reactivity, quick and simple application, and adjustment of thepressure plates. The trans-parenchymal bolt uses pressure plates thatare affixed to the ends of the bolt to distribute the pressure over awide area of tissue and compress the tissue. Key features of thepressure plates include one-way ratcheting with quick release or afriction lock, ability to quickly and cleanly remove the pressure plate,and the ability to adjust the pressure plate to ensure optimum tissueapposition and compression. The trans-parenchymal bolt generatespressure tamponade to provide for wound hemostasis. The pressure platesare atraumatic structures such as tabs, leafs, solids, meshes, or otherstructures that distribute force over a wide area of tissue. Bycontrast, traumatic structures include pointed projections or small thinwires or whiskers that could rip through parenchymal, or other, tissue.The trans-parenchymal bolt may be placed through an open surgical accesssite or through a laparoscopic access and manipulation system. Thetrans-parenchymal bolt, or bolt, can act as, perform the function of, orbe equivalent to a soft-tissue rivet. The bolt can also be placedblindly into tissue wherein the distal end of the bolt expands to form apressure plate thus eliminating the need to access the distal end of thebolt to apply the pressure plate. In this embodiment, the distalpressure plate is activated or expanded by control energy or forceapplied at the proximal end of the bolt, said control energy beingtransmitted along the length of the bolt by a linkage, coupling,electronic cabling, or the like. The control energy, or force, thenexpands the distal pressure plate. Release, or re-collapse, of thedistal pressure plate can also be accomplished using the same mechanismat the proximal end of the bolt. The distal and proximal pressure platesare not sharp but are blunted and atraumatic and apply distributedpressure to the tissue.

Once the bolt has been placed, it remains in place either temporarily orpermanently. Temporary placement necessitates removal of the bolt. Thebolt may be made from materials that permit long-term implantation or itmay be fabricated from resorbable materials that obviate the need toremove the bolt in a subsequent surgical procedure. Both the bolt andthe pressure plates are fabricated from materials with smooth outersurfaces that do not encourage tissue or clot ingrowth. The bolts andpressure plates are radiopaque and can be visualized on fluoroscopy orX-ray. Thus, the bolts and pressure plates may be removed with minimalre-bleeding.

The current medical practice of utilizing sutures is not an optimizedsolution to open visceral wound repair. Sutures were not designed foruse in parenchymal tissue. The present invention distinguishes over thecurrent medical practice because the present invention is tailored tothe needs of open visceral wound repair. The parenchymal bolts are stiffenough to serve as their own needles, trocars, or stylets. They may beflexed or permanently deformed to achieve the desired tissuecompression. They are suited for either open surgical implantation andremoval, or they are suited for laparoscopic placement and removal usingspecialized access, grasping and delivery instruments. When thetrans-parenchymal bolts of the present invention are removed from thepatient, re-bleeding does not occur because there is minimal penetrationof the wound tissues or clot into the interstices of the bolt andpressure plate.

For purposes of summarizing the invention, certain aspects, advantagesand novel features of the invention are described herein. It is to beunderstood that not necessarily all such advantages may be achieved inaccordance with any particular embodiment of the invention. Thus, forexample, those skilled in the art will recognize that the invention maybe embodied or carried out in a manner that achieves one advantage orgroup of advantages as taught herein without necessarily achieving otheradvantages as may be taught or suggested herein.

These and other objects and advantages of the present invention will bemore apparent from the following description taken in conjunction withthe accompanying drawings.

BRIEF DESCRIPTION OF THE DRAWINGS

A general architecture that implements the various features of theinvention will now be described with reference to the drawings. Thedrawings and the associated descriptions are provided to illustrateembodiments of the invention and not to limit the scope of theinvention. Throughout the drawings, reference numbers are re-used toindicate correspondence between referenced elements.

FIG. 1A illustrates a longitudinal cross-sectional view of theparenchymal bolt, according to an embodiment of the invention;

FIG. 1B illustrates a lateral cross-sectional view of the parenchymalbolt near one of the ends, according to an embodiment of the invention;

FIG. 1C illustrates a lateral cross-sectional view of the parenchymalbolt near the center, according to an embodiment of the invention;

FIG. 2A illustrates a side view of the pressure plate and locking nut incross-section, according to an embodiment of the invention;

FIG. 2B illustrates an end view of the pressure plate and locking nutalso showing the lock release, according to an embodiment of theinvention;

FIG. 3 illustrates a longitudinal cross-sectional view of theparenchymal bolt, two pressure plates and two locking nuts, according toan embodiment of the invention;

FIG. 4 illustrates a longitudinal cross-sectional view of theparenchymal bolt, two pressure plates and two locking nuts wherein theparenchymal bolt has been malleably deformed into a right angle bend,according to an embodiment of the invention;

FIG. 5A illustrates a typical wound to the liver, according to anembodiment of the invention;

FIG. 5B illustrates preparations for open access liver wound hemostasisusing three parenchymal bolts, six pressure plates and six ratchetinglocks, according to an embodiment of the invention;

FIG. 5C illustrates the wound to the liver following temporary repairwith three parenchymal bolts, six pressure plates, and six ratchetinglocks, according to an embodiment of the invention;

FIG. 6A illustrates a wound to the liver being repaired throughlaparoscopic access by application of a parenchymal bolt, according toan embodiment of the invention;

FIG. 6B illustrates application and tightening of a pressure plate andratcheting lock via laparoscopic instrumentation, according to anembodiment of the invention;

FIG. 6C illustrates the wound to the liver following laparoscopicplacement of three parenchymal bolts, six pressure plates, and sixratcheting locks, according to an embodiment of the invention;

FIG. 7A illustrates a side cross-sectional view of a parenchymal tissueinjury with a parenchymal bolt, two pressure plates, and two ratchetinglocks prior to tightening, according to an embodiment of the invention;

FIG. 7B illustrates a side cross-sectional view of the parenchymaltissue injury during tightening of the ratcheting locks, according to anembodiment of the invention;

FIG. 8 illustrates a longitudinal cross-sectional view of a parenchymalbolt comprising pressure plates and friction locks, according to anembodiment of the invention;

FIG. 9A illustrates a side cross-sectional view of a parenchymal boltcomprising a distal pressure plate that is integral to the bolt andopens to apply pressure to tissue once the bolt has been placed throughtissue or released, according to an embodiment of the invention;

FIG. 9B illustrates a side cross-sectional view of a parenchymal boltcomprising a distal pressure plate that is integral to the bolt and hasopened following partial withdrawal of the sharp trocar, according to anembodiment of the invention; and

FIG. 10 illustrates a side view of a delivery system for a soft tissuebolt, shown in partial breakaway view, according to an embodiment of theinvention.

DETAILED DESCRIPTION OF THE INVENTION

The present invention may be embodied in other specific forms withoutdeparting from its spirit or essential characteristics. The describedembodiments are to be considered in all respects only as illustrativeand not restrictive. The scope of the invention is therefore indicatedby the appended claims rather than the foregoing description. Allchanges that come within the meaning and range of equivalency of theclaims are to be embraced within their scope.

FIG. 1A illustrates a longitudinal cross-sectional view of a parenchymalbolt 10 of the present invention. The parenchymal bolt 10 comprises aninner core 12, an outer coating 14, a central region 16, a plurality ofends 18, and a plurality of serrations 20 on one or both ends 18. Theparenchymal bolt 10 further comprises an optional pointed tip or trocar22.

Referring to FIG. 1A, inner core 12 of the parenchymal bolt 10 iscoaxially affixed to interior of the outer coating 14. The centralconnecting region 16 is disposed between the ends 18. One or more of theends 18 of the parenchymal bolt 10 comprise a plurality of serrations 20disposed longitudinally, along at least one side of one or more ends 18.The optional pointed tip or trocar 22 is removably affixed coaxially toone or more of the ends 18.

Referring to FIG. 1A, the inner core 12 of the parenchymal bolt 10provides column strength and the ability to be malleable or elastomeric,depending on the patient requirements. The preferred configuration ofthe inner core 12 is that it is malleable and located in the centralregion 16 only. The ends 18 are, preferably, elastomeric and do not havethe malleable inner core 12 disposed therethrough. Another importantadvantage of having only polymeric material comprise the ends 18 is thatthe ends can be cut off or trimmed to size once the parenchymal bolt 10is fully installed or placed in the patient. Column strength isimportant so that tension may be transmitted through the parenchymalbolt 10, even when the parenchymal bolt 10 has been bent into an arc.Column strength also permits the parenchymal bolt 10 to be forcedthrough tissue much the same as a suture needle would be forced throughtissue. Malleability is important so that the parenchymal bolt 10 can bebent into the correct curvature needed for optimum coaptation of thetissue being repaired.

The inner core 12 is fabricated from materials such as stainless steel,cobalt-nickel alloys, nitinol, tantalum, titanium, polylactic acid,polyglycolic acid, platinum, and the like. The inner core 12 ispreferably radiopaque and visible under fluoroscopy or X-Ray. It isimportant that the parenchymal bolt 10 be radiopaque.

The outer coating 14 is fabricated from the same materials as are usedto fabricate the inner core 12. The outer coating 14 may be the samephysical structure as the inner core 12. Preferably, the outer coating14 is smooth and does not allow tissue ingrowth. The outer coating 14may be fabricated from polymers such as, but not limited to,polypropylene, polyethylene, polyester, polyurethane, polylactic acid,polyglycolic acid, polyimide or copolymers of these materials. In apreferred embodiment, the bolt 10 comprises radiopaque markers. Themarkers are fabricated from tantalum, gold, platinum, stainless steel,titanium, nitinol, cobalt nickel alloys and the like. The markers showthe extents of the outer coating 14. The addition of barium, bariumcompounds, or the like in concentrations of up to about 40% in thepolymer provides for radiopacity.

One or more of the ends 18 comprise an optional sharpened or tapered tip22 to pierce tissue with minimal resistance. The optional pointed tip ortrocar 22 facilitates passage of the parenchymal bolt 10 through tissue.The pointed tip or trocar 22 may be removed to minimize further tissuedamage while the parenchymal bolt 10 is in place. In a preferredembodiment, the pointed tip or trocar 22 is removably attached to theends 18 by a male threaded stub that is mated into a female threadedadapter on the end 18. A bayonet mount is another suitable method ofattaching the pointed tip or trocar 22 to the end 18. In anotherembodiment, the pointed tip or trocar 22 may also be longitudinallydisposed through the entire core of the parenchymal bolt 10 and isremoved by simply withdrawing the trocar 22 from the parenchymal bolt10. The removable sharp tip 22, in a further embodiment, is retractablewithin the end 18 of the parenchymal bolt 10. Retraction of the sharptip 22 is either automatic or manually activated.

One or more of the ends 18 comprise the plurality of serrations 20 thatpermit locking with devices that are attached to the parenchymal bolt 10in a later process. The serrations 20 are, preferably, triangular inshape and project outward from the longitudinal axis of ends 18. In thepreferred embodiment, the serrations 20 comprise triangular projections.One side of the triangular projection is perpendicular to thelongitudinal axis of the end 18. The perpendicular side of the trianglemay also be undercut. Another side is tapered away from the end 18 andforms a ramp moving inward from the end 18 toward the center 16 of theparenchymal bolt 10.

FIG. 1B illustrates a cross-section of the parenchymal bolt 10 takennear one of the ends 18. The cross-sectional view of the end 18 furthercomprises one or more optional tracking grooves 24 and one or moreoptional longitudinal ratchet slots 25.

Referring to FIG. 1B, the tracking groove 24 is a slot and is disposedlongitudinally along the length of ends 18. The longitudinal ratchetslot 25 is disposed longitudinally along the length of ends 18.

Referring to FIGS. 1A and 1B, the serrations 20 are disposed within theratchet slot 25. The ratchet slot 25 holds and hides the serrations fromthe tissue as the parenchymal bolt 10 is advanced through the tissue tominimize trauma. The tracking groove 24 is used to provide alignment forparts that will be mated to the parenchymal bolt 10. By having two setsof tracking grooves 24, bilateral symmetry is achieved and parts can bemated in two orientations, rather than just one, thus facilitating themating process. One ratchet slot 25 is required for each set ofserrations and two ratchet slots 25 permit orientation of mating partsin more than one orientation. When more than one ratchet slot 25 andtracking groove 24 are used on each end, the second slot 25 or groove 24is disposed 180 degrees around the end 18 circumference from the firstslot 25 or groove 24.

FIG. 1C illustrates a cross-section of the central region 16 of theparenchymal bolt 10. The central region 16 comprises the core 12 and theouter coating 14. The outer coating 14 is disposed coaxially around thecore 12. The optional tracking grooves 25 are not shown in thiscross-section.

FIG. 2A illustrates a cross-sectional view of a pressure plate 26 and aratcheting lock 28. The pressure plate 26 further comprises one or morepass through holes 30. The ratcheting lock 28 further comprises aplurality of locking tabs 32, a tracking protrusion 34, and a centralhole 36.

The ratcheting lock 28 is disposed coaxially with the pass through hole30 on the pressure plate 26. The ratcheting lock 28 is either affixed tothe pressure plate 26, is integral to said pressure plate 26, or ismounted separately outside the pass through hole 30 of said pressureplate 26. The locking tabs 32 are flexibly affixed to the ratchetinglock 28 and project inward with a vertical edge toward the pressureplate 26 and a ramped edge sloping away from the pressure plate 26. Thetracking protrusion 34 is one or more small projections into the centralhole 36 of the ratcheting lock 28.

The pressure plate 26 may have a single pass through hole 30 or it mayhave the plurality of pass through holes 30. With the plurality of passthrough holes 30, one pressure plate 26 can be used with multipleparenchymal bolts 10.

Referring to FIGS. 1A, 1B, and 2A, the end 18 is configured to mate withthe ratcheting lock 28 and the pressure plate 26. When the ratchetinglock 28 is advanced over one of the ends 18, through the central hole36, the flexible locking tab 32 on the ratcheting lock 28 is bent asideby the ramp formed on the outside of serrations 20 and allowsadvancement of the ratcheting lock 28 to continue. Pulling backward onthe ratcheting lock 28 or pressure plate 26 causes the vertical edge ofthe locking tab 32 to dig into the perpendicular sides described by theinner edges of the serrations 20 on the ends 18 so the ratcheting lock28 will not slip backwards. The tracking protrusion 34 slideably mateswith the alignment groove 24 on the end 18 to prevent the locking tabs32 from becoming misaligned with the serrations 20 and inadvertentlydisengaging.

FIG. 2B illustrates an end view of the pressure plate 26 and theratcheting lock 28. As seen in this view, the ratcheting lock 28 furthercomprises a lock release 38.

Referring to FIGS. 2A and 2B, the locking tabs 32 project inward towardthe center of the central hole 36 in the ratcheting lock 28. The lockrelease 38 is activated by manual pressure or by a laparoscopicinstrument to bend back and release the locking tab 32 from theserrations 20 so that the ratcheting lock 28 and pressure plate 26 maybe removed from the end 18. The lock release 38 allows for quick releaseof the ratcheting lock 28 and pressure plate 26. In another embodiment,the lock release 38 retracts the tracking protrusions 34 so that theratcheting lock 28 can be rotated to disengage the locking tabs 32 fromthe serrations 20 and enable removal of the ratcheting lock 28 and thepressure plate 26 from the parenchymal bolt 10.

The pressure plate 26, the ratcheting lock 28 and the lock release 38are fabricated from the same materials as are used in fabrication of theparenchymal bolt 10. All parts are designed with smooth outer surfacesto minimize the opportunity for tissue or thrombus ingrowth. Thepressure plate 26 is stiff enough to distribute pressure to gently holdthe tissue together while it heals. In a preferred embodiment, thepressure plate 26 and the ratcheting lock 28 are radiopaque. Materialssuch as barium, barium compounds, or radiopaque metals or the like,comprise at least part of the pressure plate 26 or lock 28.

Referring to FIGS. 1A, 1B, 1C, 2A and 2B, the length of the parenchymalbolt 10 ranges from 0.5 cm to 500 cm depending on the tissue beingcompressed. More preferably, the length of the parenchymal bolt 10ranges from 2 cm to 50 cm. The diameter of the parenchymal bolt 10varies and is in proportion to the length of the bolt 10. Diameterranges of between 0.5 mm and 10 mm are appropriate for the parenchymalbolt 10. The pressure plate 26 is sized to the organ being compressed.The pressure plate 26 has roughly rectangular dimensions ranging from aminimum of 0.5 cm to a maximum of 100 cm. The preferred range of sizesfor the pressure plate 26 is 1 cm to 20 cm. The pressure plate 26thickness ranges from 0.5 mm to 30 mm.

FIG. 3 illustrates a longitudinal cross-sectional view of theparenchymal bolt 10 with two pressure plates 26 and two ratcheting locks28. The pointed tip or trocar 22 has been removed in this view. Thepressure plates 26 and ratcheting locks 28 have been pushed over theends 18 of the parenchymal bolt so that the locking tabs 32 have engagedthe serrations 20.

FIG. 4 illustrates a longitudinal cross-sectional view of theparenchymal bolt 10 with two pressure plates 26 and two ratcheting locks28. The parenchymal bolt 10 has been malleably deformed in its centralregion 16 and maintains that shape because the core 12 has sufficientstrength to overcome the elastic forces generated by the outer covering14.

FIG. 5A illustrates a wound 42 in a liver tissue 40. The liver is aprime example of parenchymal tissue that often receives damage duringabdominal trauma. Note that the parenchymal tissue of the liver 40 isfriable and unable to sustain high stresses without fracturing ortearing.

FIG. 5B illustrates open surgical preparation for repair of the liverwound 42 according to the methods of the present invention. In thiscase, three parenchymal bolts 10, six pressure plates 26 and sixratcheting locks 28 are prepared for the procedure while the liver 40apposition is accomplished with manual pressure.

FIG. 5C illustrates completion of the repair of the wound 42 to theliver 40 using the parenchymal bolts 10, pressure plates 26 andratcheting locks 28. The ratcheting locks 28 are tightened sufficientlyto hold the pressure plates 26 firmly against the tissue causingcomplete wound 42 closure and hemostasis.

FIG. 6A illustrates the wound 42 to the liver 40 with the parenchymalbolt 10 being applied by a laparoscopic instrument 44. In thisembodiment, the laparoscopic instrument 44 is a grasper or set of jaws,placed through an axially elongate hollow structure 48, that may bemanipulated by the surgeon from the outside of the patient.

FIG. 6B illustrates the wound 42 to the liver 40 following placement ofthe first parenchymal bolt 10, two pressure plates 26 and two ratchetinglocks 28 using the first laparoscopic instrument 44 and a secondlaparoscopic instrument 46. Again, the laparoscopic instruments 44 and46 are placed through an axially elongate hollow structure 48 thatprovides access to the internal organs of the patient. The laparoscopicgrasping device 46 is placed around the ratcheting lock 28 and is usedto advance the ratcheting lock 28 and pressure plate 26 inward againstthe liver tissue 40. The laparoscopic grasping device 44 applies tensionto the parenchymal bolt 10 so that the pressure plate 26 and theratcheting lock 28 move relative to the parenchymal bolt 10. Thelaparoscopic grasping instruments 44 and 46, which may be similar tovery long nosed pliers, may be replaced by a single instrument thatperforms both functions of stabilizing the parenchymal bolt 10 andadvancing the ratcheting lock 28. This type of procedure is generallyperformed under direct vision through a lens and illuminator placedlaparoscopically within the surgical field.

FIG. 6C illustrates the wound 42 to the liver 40 following laparoscopicrepair with three parenchymal bolts 10, six pressure plates 26 and sixratcheting locks 28.

FIG. 7A illustrates a side cross-sectional view of the wound 42 toparenchymal tissue 40, in this case the liver 40, following initialrepair with the parenchymal bolt 10 of the present invention. The repairof the wound 42 comprises placement of the parenchymal bolt 10 followedby placement of two pressure plates 26 and two ratcheting locks 28.

Referring to FIG. 7A, FIG. 1A and FIG. 2A, the pointed tip or trocar 22has been removed or retracted following full tissue 40 penetration bythe parenchymal bolt 10. Two pressure plates 26 have been applied to theends 18 of the parenchymal bolt 10 to transfix the tissue 40. Tworatcheting locks 28 are in the process of being tightened over thepressure plates 26 and the wound 42 is still open.

FIG. 7B illustrates the wound 42 in the parenchymal tissue 40 at a pointwhere the ratcheting locks are nearly tightened against the tissue 40.The wound 42 has achieved nearly complete closure. Additional inwardtightening of the ratcheting locks 28 will compress the pressure plates26 and achieve full wound 42 closure and hemostasis. The parenchymalbolt 10 flexes to accommodate the change in wound geometry as theratcheting locks 28 are tightened.

FIG. 8 illustrates another embodiment of the parenchymal bolt 10, shownin longitudinal cross-section. The parenchymal bolt 10 further comprisesan axially elongate shaft 14, a malleable central component 12, asharpened tip 22, one or more pressure plates 26, and one or morefriction locks 50. The friction lock 50 further comprises a frictiongenerator 52 and a housing 54, which further comprises a grasping bump56.

The key enhancement to this embodiment of the parenchymal bolt 10 is thefriction lock 50. The friction lock 50 may be separate or integral tothe pressure plate 26. The friction lock 50 is fabricated frombiocompatible polymeric materials such as, but not limited topolyethylene, polypropylene, ABS, PVC, stainless steel, PTFE, titanium,polylactic acid (PLA), polyglycolic acid (PGA), and the like. The PLA orPGA fall under a class of materials that are bioresorbable. Thesebioresorbable, or resorbable, materials will absorb when implanted inbody tissue, over a period of time extending from 1 day to 6 months,preferably in the range of 1 week to 3 months. The formulation of thebioresorbable materials can be modified to adjust the resorption time.Other bioresorbable materials include those fabricated with sugars,collagen, protein, or the like. In the preferred embodiment, thefriction lock 50 comprises a friction generator 52, which is a disc witha hole in the center. The hole is smaller in diameter than the outsidediameter of the axially elongate shaft 14 of the parenchymal bolt 10.The friction generator 52 comprises elastomeric materials that exert aninward pressure and generate friction against the outside diameter ofthe axially elongate shaft 14. Such elastomeric materials include, butare not limited to, polyurethane, silicone elastomer, latex rubber, andthe like. The friction exerted by the friction lock 50 against theaxially elongate shaft 14 is sufficient to resist the force of thetissue resilience once engaged in contact but insufficient to preventmanual movement generated by the surgeon either applying or removing thefriction lock 50 from the axially elongate shaft 14. The housing 54further comprises a grasping surface 56, which is a bump or otherfeature that allows for easy grasping by the surgeon in a wet or slickenvironment so that the friction lock 50 may be removed retrograde fromthe shaft 14 of the parenchymal bolt 10. Other embodiments of thefriction lock 50 include those that comprise a jam cleat, an over-centercam, a spring-loaded friction member, and the like. The friction lock 50preferably does not comprise a release mechanism but in certainconfigurations, a button or latch to release the friction is required.

FIG. 9A illustrates another embodiment of a parenchymal bolt 100 with adistal pressure plate 90 that is pre-affixed to the bolt 100 prior touse in a patient. The bolt 100 comprises a shaft 14, a trocar 80 furthercomprising a sharp tip 82 and a trocar handle 84, at least one distalpressure plate 90, a connection region 86, a proximal pressure plate 26,a lock 50, and an actuation lever 100.

The distal pressure plate 90 is configured to fold against the shaft 14of the bolt 100 when the bolt 100 is being inserted distally throughtissue. When the bolt 100 distal end, which carries the distal pressureplate 90, has been advanced through the tissue and is released, thedistal pressure plate 90 opens, at least partially due to spring forceapplied, and can exert pressure on the tissue when pulled proximally.The distal pressure plate 90 is affixed to the shaft 14 by theconnection region 86, which can be bendable, can comprise a spring, cancomprise an actuator, can comprise releasable locks, or can comprise ahinge. The shaft 14 can be malleable, elastomeric, rigid, pre-bent,shape-memory such that it takes a curved configuration upon exposure tobody temperature or a temperature above body temperature generated byOhmic heating, or the like.

The distal pressure plate 90, in this embodiment, comprises narrowplates or arms that are separated from the shaft 14 by slots or gapsthat allow for expansion of all but the distal region of the pressureplate 90 where it is affixed to the shaft 14 at the connection region86. In an embodiment, the distal pressure plate 90 can be integral tothe shaft 14 and be created by slits or slots in the shaft 14 to formthe distal pressure plate 90 elements. The distal pressure plate 90expandable elements can be held against the side of the shaft 14 byreleasable locks, such as those that release or are activated when thetip 82 is withdrawn proximally. The proximal pressure plate 26 and lock50 are applied in the same way as that of other embodiments of theparenchymal bolt 10. In the preferred embodiment, the proximal pressureplate 26 and lock 50, which can be a friction lock, are pre-positionedon the shaft 14 of the parenchymal bolt 100 or applier and is advancedby the bolt applier, laparoscopic instrument, or manually by thesurgeon. In an embodiment the parenchymal bolt 100 can be applied by aninstrument such as a bolt applier, laparoscopic instrument, or the like(FIG. 10). This embodiment can be useful when the distal side of thetissue is not easily accessed by the surgical approach and placement ofthe distal pressure plate 90 would be difficult or impossible. In anembodiment, the sharp pointed tip 82 is retractable or is withdrawnproximally by the user by pulling on the trocar handle 84 affixed toshaft 80 and further affixed to tip 82 once the tissue has beenpenetrated. The length of the bolt 100 can be adjusted by trimming withthe bolt applier or other instrument such as a cutter or pair ofscissors. In another embodiment, the length of bolt 100 can also beadjusted using a telescoping, locking configuration in the shaft 14. Thetelescoping shaft 14 eliminates the need for length trimming. This typeof bolt 100 can be used to affix prosthetic devices to soft tissue. Theactuator lever 100 is affixed near the proximal end of the shaft 14 andcan be moved, either by hand or by an instrument, to force the distalpressure plates 90 outward to engage the tissue.

FIG. 9B illustrates a cross-section of the bolt 100 of FIG. 9A with thedistal pressure plate 90 expanded or released. The bolt 100 comprisesthe shaft 14, the trocar 80, the sharp tip 82, the proximal pressureplate 26, the lock 50, the distal pressure plates 90, the connectionregion 86, the actuation lever 150, an actuation linkage 102, a linkagelumen 104, one or more lever arms 106, a lever arm hinge 108, anoptional distal pressure plate hinge 110, and one or more shaft windows112.

Referring to FIG. 9B, the distal pressure plate 90, in this embodiment,will appear as a series of radial projections or fingers. Integral orseparate leaf springs 86 bias the expandable elements of the distalpressure plate 90 to expand outward. The pointed distal tip 82 and itsshaft 80 are slidably movable within the shaft 14. In a preferredembodiment, one or more detents in the shaft 14 mate with protrusions inthe shaft 14 to provide a positive positioning index that may beovercome by manual force. In one embodiment, when the distal pressureplate 90 passes beyond tissue, the spring biased pressure plate elementsopen. In another embodiment, the pressure plate 90 is released when thepointed distal tip 82 and its shaft 80, which are affixed to each other,are withdrawn proximally. The connection region 86 can comprise aspring, an actuator, releasable locks to keep the pressure plates 90open, or a hinge.

In another embodiment, when the control, or actuation, lever 150 isadvanced forward, it forces the actuation linkage 102 to slide distallywithin the linkage lumen 104 and advance the proximal end of theactuation levers 150. Distal motion of the actuation levers 150 forcesthe distal pressure plates 90 to open outward around the distal pressureplate hinge 110. Friction in the system or a lever lock 86, which can bereleasable and controllable from the proximal end of the bolt 10, ornon-releasable, keeps the distal pressure plates 90 open such that theyproject laterally away from the shaft 14. Backup reinforcements, such asthe lever arms 106 prevent the leafs of the distal pressure plate 90from rotating substantially beyond a plane perpendicular to the axis ofthe bolt 100.

The distal pressure plates 90 can be configured as wings as shown, orthey can be bendable or hinged in the middle such that they openradially or laterally when force is applied at the proximal end of thedistal pressure plates 90. In this embodiment, the proximal end of thepressure plate 90, which is constrained not to expand radially is moveddistally causing the center of the distal pressure plates 90 to bend,bow, or hinge. This arrangement, similar in configuration to aMoly-bolt, for example, can provide for distal fixation and apressure-plate effect. Transmission of power from the actuation lumen104 to the lever arms 106 or distal pressure plates 90, which do not usethe lever arm 106, can occur through a window 112 cut in the side of theshaft 14. In yet another embodiment, the distal pressure plates 90comprise shape memory nitinol that is shape-set during heat-treating toexpand radially at body temperature. The nitinol-actuated pressureplates 90 can also be configured to expand radially with the applicationof electrical energy to the pressure plates 90 causing Ohmic orresistive heating of the nitinol elements above body temperature past atransition temperature, such as the austenite start temperature oraustenite finish temperature. The nitinol-actuated pressure plates 90can be heated using adjunctive heaters such as a nickel chromium wirerouted around or near the nitinol actuator. Hysteresis effects can keepthe nitinol open even when the bolt 100 or pressure plates 90 areexposed to body temperatures or slightly below. The pressure plates 90in this embodiment can take the shape of ribbons or wings that arelongitudinally disposed along the shaft 14 but bend outward radially orlaterally to cause the pressure plate effect. The pressure plates 90 canalso take the form of a coil of wire that expands to form a ball orother three-dimensional mesh which can serve the function of a pressureplate.

In an embodiment, the proximal pressure plate 26 can be configured asthe mirror image of the distal pressure plate 90. In this embodiment,the proximal pressure plate 26 is actuable, rather than beingpre-attached to the shaft 14 with the lock 50. The proximal pressureplate 26 of this embodiment can be a Moly-bolt, a balloon, an expandingwire structure or other configuration similar to that described for thedistal pressure plate 90 using the same or similar actuation mechanismsor means. In another embodiment, the bolt 100 can be configured to bendin response to shape memory actuators affixed thereto. The actuation ofthe shape memory actuators can be performed using electrical energydelivered through a delivery system such as that shown in FIG. 10.

Another aspect of the inventions includes the method of use of the bolt10. In an embodiment, the bolt 100 is inserted into a patient throughthe tissue using the fingers or with the aid of an instrument which isaxially elongated to provide additional reach into small, narrow spacesunreachable except through undesirable open surgery. The bolt 100 isadvanced with its sharp tip 82 exposed through tissue until it hasachieved the desired penetration. The sharp tip 82 is then retracted andoptionally completely withdrawn from the bolt 100. The distal pressureplates 90 are expanded by actuation from the proximal end, by automaticmeans such as shape memory expansion, or by proximal pullback or removalof the core, sharp trocar 80. Proximal end pressure plates 26 are eitherapplied, actuated, or expanded using the same or similar means as thedistal pressure plates 90. The plates can be adjusted for tightness bycausing the proximal pressure plate 26 to slide axially along the shaft14 and then lock in place with the lock 50. The instrument or hand isthen decoupled from the bolt 100 and removed. The bolt 100 is eitherleft permanently, removed by surgery, or left to resorb into the tissue.The bolt 100 can be used to repair damaged parenchymal tissue, or it canbe used to repair damaged muscle such as smooth muscle or striatedmuscle. The use of soft tissue rivets, such as the bolt 100, can be usedto speed closure of wounds that result from trauma or surgery. Theapplication of a rapid-fire bolt 100 by means of an installation tool(not shown) can result in placement of multiple bolts 100 in a veryshort period of time. For example, it is possible to place 5 to 20 bolts100 in one minute or up to one rivet or bolt 10 every 5 seconds usingthis type of system.

FIG. 10 illustrates a delivery system 1000 for a soft tissue bolt 100comprising a main shaft 1002, a pushrod 1004, a distal engagement tab1006, a grabber control handle 1008, a pushrod control handle 1010, anactuator control lever 1012, a main handle 1014, one or more graspertabs 1018, a grasper hinge 1020, one or more grasper linkages 1022, oneor more grasper linkage connectors 1024, one or more electrical inputjack 1026, and one or more grasper electrode 1028.

Referring to FIG. 10, the main handle 1014 is affixed to the main shaft1002 near the proximal end of the main shaft 1002. The pushrod 1004 isaffixed, at or near its proximal end to the pushrod control handle 1010and at or near its distal end, to the distal engagement tab 1006. Thepushrod 1004 is slidably disposed within or near the main shaft 1002,with respect to which it is oriented generally parallel. The graspertabs 1018 are rotatably affixed about the grasper hinge 1020, which isaffixed near the distal end of either the main shaft 1002 or the pushrod1004. The grasper linkages 1022 are affixed to the grasper tabs 1018 atlinkage connectors 1024. Electrical input jack 1026 is affixed to themain handle 1014, the pushrod control handle 1010, or near the proximalend of the main shaft 1002. The grasper electrodes 1028 are affixed toeither the grasper tabs 1018 or the distal engagement tab 1006 and areoperably connected to the electrical input jacks 1026 by an electricalbus, which can be, in the illustrated embodiment the grasper linkages1022.

The delivery system 1000 can be used in conjunction with a laparoscopicor thoracoscopic trocar, for example, or through an open surgical portto deliver the soft tissue bolt 100 to a surgical target site. Referringto FIGS. 9A and 9B, the operator grasps the delivery system 1000 by themain handle 1014 with the distal engagement tab 1006 releasably engagingthe distal pressure plate 90 expansion control lever 150 on the bolt100. In another embodiment, the distal graspers can be used toreleasably engage the distal pressure plate 90 control lever 150 on thebolt 100. In this embodiment, the distal engagement tab 1006 can be usedto withdraw the obturator, shaft 80, or sharpened point of the bolteither partially or fully proximal and out of the bolt 100. In thisembodiment, the grasper electrodes 1028 can be used to deliverelectrical energy to either bend the bolt 100 or to radially expand thedistal pressure plates 90 by shape memory effects using nitinol, or thelike in one or both applications. The distal engagement tab 1006 or thegrasper tabs 1018 can be configured, in one or more embodiments, toprovide cutting action to cut off excess length of the soft tissuerivet, or bolt, 100 during or after the implantation and securingprocess has been completed. Alternatively, an additional cutter 1030 canbe affixed near the distal end of the delivery system 1000 to cut thebolt 100 to length. This is facilitated by removal of any metallic corematerials leaving primarily polymeric bolt 100 shaft materials, whichcan more easily be severed. Control over the cutting action is appliedat or near the proximal end of the delivery system 1000 and the controlis transmitted to the cutting mechanism by linkages such as the grasperlinkages 1022 or the pushrod 1004.

The components of the delivery system 1000 can be fabricated frompolymeric materials such as, but not limited to, polycarbonate,polypropylene, polyethylene, PEEK, polyvinyl chloride, acrilonitrilebutadiene styrene, polysulfone, or the like. The components can also befabricated in part, or in whole from metals such as, but not limited to,stainless steel, cobalt nickel alloy, titanium, nickel titanium,tantalum, or the like. The length of the main shaft can range from 2 cmto 50 cm and the diameter of the main shaft can range from 1 mm (3French) to 25 mm (75 French). The delivery system 1000 can be releasablyaffixed to the bolt 100 in singles. In another embodiment, multiplebolts 100 can be loaded into the delivery system to permit rapid fire,multiple applications. The delivery system 1000 can control theexpansion of the distal, or second, pressure plate. The delivery system1000 can control retraction of the obturator. The delivery system 1000can control bending of the bolt 100.

Application of the parenchymal bolt system provides improved speed ofsolid organ trauma repair and minimizes the chance of tissue tearing orfracture, relative to the use of sutures for said repair. Theparenchymal bolt system provides pressure tamponade to the injuredtissue to provide for hemostasis and maximize the recovery process whileminimizing complications common to suture-based approaches.

The present invention may be embodied in other specific forms withoutdeparting from its spirit or essential characteristics. For example, theratcheting locks could be replaced by simple threaded nuts that engagethreads on the parenchymal bolt. The distal pressure plate can compriseone or more radially expandable wings such as are found in a hollow wallanchor, or the distal pressure plate can comprise a fluid-filled balloonsuch as a non-elastomeric balloon or an elastomeric, Foley-type balloon,or they can be of a radially different shape such as a three-dimensionalwire mesh or a solid such as when a hydrogel, constrained within a waterpermeable membrane, expands due to fluid uptake to swell into a flexiblevolume. The described embodiments are to be considered in all respectsonly as illustrative and not restrictive. The scope of the invention istherefore indicated by the appended claims rather than the foregoingdescription. All changes that come within the meaning and range ofequivalency of the claims are to be embraced within their scope.

1. An apparatus adapted for achieving closure of soft tissue woundscomprising: an axially elongate bolt having a first end and a secondend, wherein the bolt comprises a malleable inner core limited to acentral region, and an outer polymeric coating disposed coaxially aroundthe core, the outer coating axially extending beyond the central regionto the first and second end; a first pressure plate attached onto thefirst end of the bolt, wherein the first pressure plate is fixed at alocation axially along the bolt; a second pressure plate attached to thesecond end of the bolt, wherein the second pressure plate iscontrollably movable axially along the bolt; and a lock forlongitudinally fixing the second pressure plate along the length of thebolt; wherein the first and second pressure plates are atraumaticstructures.
 2. The apparatus of claim 1 wherein the first pressure plateis radially outwardly expandable and further wherein said radiallyoutward expansion of the first pressure plate is controlled at the firstend of the bolt.
 3. The apparatus of claim 1 wherein the first pressureplate is radially outwardly expandable when the first pressure plate isembedded within tissue.
 4. The apparatus of claim 1 wherein said bolt ismalleably bendable in a direction perpendicular to its longitudinalaxis.
 5. The apparatus of claim 1 wherein the second end of the bolt isexposed outside tissue when the second pressure plate is applied andwhere the first end of the bolt is not exposed outside tissue when thefirst pressure plate is radially outwardly expanded.
 6. The apparatus ofclaim 1 wherein said lock comprises a quick release mechanism.
 7. Theapparatus of claim 1 wherein said bolt further comprises a removable orretractable sharp tip.
 8. The apparatus of claim 1 wherein an outersurface of the bolt is smooth and discourages tissue ingrowth.
 9. Theapparatus of claim 1 wherein the outer surface of the bolt comprises apolymeric material.
 10. The apparatus of claim 9 wherein said polymericmaterial is selected from a group including polyurethane, polyethylene,polypropylene, silicone rubber, polyester polymethylmethacrylate,polyvinyl chloride, or a copolymer including of one of these materials.11. The apparatus of claim 4 wherein said malleable bendability isfacilitated by an axially elongate metal support structure.
 12. Theapparatus of claim 4 wherein said malleable inner core is selected fromthe group consisting of stainless steel, nitinol, cobalt nickel alloy,titanium, and tantalum.
 13. The apparatus of claim 1 wherein said boltis radiopaque.
 14. The apparatus of claim 1 wherein the first and secondpressure plate and lock are radiopaque.
 15. The apparatus of claim 3wherein the bolt, the first and second pressure plate, and the lockcomprise bioresorbable materials.
 16. The apparatus of claim 1 furthercomprising an axially elongate support structure fabricated from shapememory material, such that following, during, or prior to implantation,the bolt can be forced to bend laterally to its longitudinal axis due toshape memory transition effects within the shape memory material.
 17. Amethod of achieving wound hemostasis and closure of soft body tissuecomprising the steps of: Applying a bolt, wherein the bolt comprises asingle, axially elongate shaft having a distal, pointed end, and aproximal end, through tissue near a wound wherein the proximal end ofthe bolt is exposed outside the tissue; expanding a first pressure plateaffixed near the distal, pointed end of the shaft; applying a secondpressure plate to the proximal end of the shaft, wherein the second endof the shaft extends beyond the second pressure plate; adjusting theposition of the second pressure plate to maintain compression againsttissue disposed between the first and second pressure plates to achievewound closure and hemostasis; and actuating a lock to secure the secondpressure plate to the shaft; wherein the bolt comprises a malleableinner core limited to a central region, and an outer polymeric coatingdisposed coaxially around the core, the outer coating axially extendingbeyond the central region to the first and second end.
 18. The method ofclaim 17 further comprising the step of retracting a sharp tip at thedistal, pointed end of the bolt such that the distal end is no longpointed, wherein retraction is controlled from the proximal end of thebolt.
 19. The method of claim 17 further comprising the step of bendingthe bolt such that the axially elongate shaft comprises a curve along atleast a portion of its length;
 20. The method of claim 17 furthercomprising the step of applying the bolt with a delivery instrument.